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                <h1 id="firstHeading" class="firstHeading">list initialization <span class="t-mark-rev t-since-cxx11">(since C++11)</span>
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<p>Initializes an object from braced-init-list
</p>
<table id="toc" class="toc"><tr><td>
<div id="toctitle"><h2>Contents</h2></div>
<ul>
<li class="toclevel-1 tocsection-1">
<a href="list_initialization.html#Syntax"><span class="tocnumber">1</span> <span class="toctext">Syntax</span></a>
<ul>
<li class="toclevel-2 tocsection-2"><a href="list_initialization.html#direct-list-initialization"><span class="tocnumber">1.1</span> <span class="toctext">direct-list-initialization</span></a></li>
<li class="toclevel-2 tocsection-3"><a href="list_initialization.html#copy-list-initialization"><span class="tocnumber">1.2</span> <span class="toctext">copy-list-initialization</span></a></li>
</ul>
</li>
<li class="toclevel-1 tocsection-4"><a href="list_initialization.html#Explanation"><span class="tocnumber">2</span> <span class="toctext">Explanation</span></a></li>
<li class="toclevel-1 tocsection-5"><a href="list_initialization.html#Narrowing_conversions"><span class="tocnumber">3</span> <span class="toctext">Narrowing conversions</span></a></li>
<li class="toclevel-1 tocsection-6"><a href="list_initialization.html#Notes"><span class="tocnumber">4</span> <span class="toctext">Notes</span></a></li>
<li class="toclevel-1 tocsection-7"><a href="list_initialization.html#Example"><span class="tocnumber">5</span> <span class="toctext">Example</span></a></li>
<li class="toclevel-1 tocsection-8"><a href="list_initialization.html#See_also"><span class="tocnumber">6</span> <span class="toctext">See also</span></a></li>
</ul>
</td></tr></table>
<h3>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: Syntax">edit</a>]</span> <span class="mw-headline" id="Syntax">Syntax</span>
</h3>
<h4>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: direct-list-initialization">edit</a>]</span> <span class="mw-headline" id="direct-list-initialization">direct-list-initialization</span>
</h4>
<table class="t-sdsc-begin">

<tr>
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</td>
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<td> <span class="t-spar">T</span> <span class="t-spar">object</span> <code><b>{ </b></code> <span class="t-spar">arg1, arg2, ...</span> <code><b>};</b></code>
</td>
<td> (1)
</td>
<td class="t-sdsc-nopad">
</td>
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<td> <span class="t-spar">T</span> <code><b>{ </b></code> <span class="t-spar">arg1, arg2, ...</span> <code><b>};</b></code>
</td>
<td> (2)
</td>
<td class="t-sdsc-nopad">
</td>
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<td colspan="10" class="t-sdsc-sep">
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<tr class="t-sdsc">
<td> <code><b>new</b></code> <span class="t-spar">T</span> <code><b>{ </b></code> <span class="t-spar">arg1, arg2, ...</span> <code><b>} </b></code>
</td>
<td> (3)
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<td class="t-sdsc-nopad">
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<td colspan="10" class="t-sdsc-sep">
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<tr class="t-sdsc">
<td> <span class="t-spar">Class</span> <code><b>{</b></code> <span class="t-spar">T</span> <span class="t-spar">member</span> <code><b>{ </b></code><span class="t-spar">arg1, arg2, ...</span> <code><b>}; }; </b></code>
</td>
<td> (4)
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<td> <span class="t-spar">Class</span><code><b>::</b></code><span class="t-spar">Class</span><code><b>() : </b></code><span class="t-spar">member</span><code><b>{</b></code><span class="t-spar">arg1, arg2, ...</span><code><b>} {...</b></code>
</td>
<td> (5)
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<td class="t-sdsc-nopad">
</td>
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<h4>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: copy-list-initialization">edit</a>]</span> <span class="mw-headline" id="copy-list-initialization">copy-list-initialization</span>
</h4>
<table class="t-sdsc-begin">

<tr>
<td colspan="10" class="t-sdsc-sep">
</td>
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<tr class="t-sdsc">
<td> <span class="t-spar">T</span> <span class="t-spar">object</span> <code><b>= {</b></code><span class="t-spar">arg1, arg2, ...</span><code><b>};</b></code>
</td>
<td> (6)
</td>
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</td>
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<td> <span class="t-spar">function</span><code><b>( { </b></code> <span class="t-spar">arg1, arg2, ...</span> <code><b>} ) ;</b></code>
</td>
<td> (7)
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<td> <code><b>return { </b></code> <span class="t-spar">arg1, arg2, ...</span> <code><b>} ;</b></code>
</td>
<td> (8)
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<td colspan="10" class="t-sdsc-sep">
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<td> <span class="t-spar">object</span><code><b>[ { </b></code> <span class="t-spar">arg1, arg2, ...</span> <code><b>} ] ;</b></code>
</td>
<td> (9)
</td>
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<td> <span class="t-spar">object</span> <code><b>= </b></code> <code><b>{ </b></code> <span class="t-spar">arg1, arg2, ...</span> <code><b>} ;</b></code>
</td>
<td> (10)
</td>
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</td>
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<td> <span class="t-spar">U</span><code><b>( { </b></code> <span class="t-spar">arg1, arg2, ...</span> <code><b>} ) </b></code>
</td>
<td> (11)
</td>
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</td>
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<td> <span class="t-spar">Class</span> <code><b>{</b></code> <span class="t-spar">T</span> <span class="t-spar">member</span> <code><b>=</b></code> <code><b>{ </b></code><span class="t-spar">arg1, arg2, ...</span> <code><b>}; }; </b></code>
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<td> (12)
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<p>List initialization is performed in the following situations:
</p>
<ul><li> direct-list-initialization (both explicit and non-explicit constructors are considered)
</li></ul>
<div class="t-li1">
<span class="t-li">1)</span> initialization of a named variable with a <i>braced-init-list</i> (that is, a possibly empty brace-enclosed list of expressions or nested braced-init-lists)</div>
<div class="t-li1">
<span class="t-li">2)</span> initialization of an unnamed temporary with a <i>braced-init-list</i>
</div>
<div class="t-li1">
<span class="t-li">3)</span> initialization of an object with dynamic storage duration with a <a href="new.html" title="cpp/language/new">new-expression</a>, where the initializer is a brace-init-list</div>
<div class="t-li1">
<span class="t-li">4)</span> in a non-static <a href="data_members.html#Member_initialization" title="cpp/language/data members">data member initializer</a> that does not use the equals sign</div>
<div class="t-li1">
<span class="t-li">5)</span> in a <a href="constructor.html" title="cpp/language/initializer list">member initializer list</a> of a constructor if <i>braced-init-list</i> is used</div>
<ul><li> copy-list-initialization (only non-explicit constructors are considered)
</li></ul>
<div class="t-li1">
<span class="t-li">6)</span> initialization of a named variable with a <i>braced-init-list</i> after an equals sign</div>
<div class="t-li1">
<span class="t-li">7)</span> in a function call expression, with <i>braced-init-list</i> used as an argument and list-initialization initializes the function parameter</div>
<div class="t-li1">
<span class="t-li">8)</span> in a <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">return</span></span></span> statement with braced-init-list used as the return expression and list-initialization initializes the returned object</div>
<div class="t-li1">
<span class="t-li">9)</span> in a <a href="operator_member_access.html#Built-in_subscript_operator" title="cpp/language/operator member access">subscript expression</a> with a user-defined <code>operator[]</code>, where list-initialization initializes the parameter of the overloaded operator</div>
<div class="t-li1">
<span class="t-li">10)</span> in an <a href="operator_assignment.html#Builtin_direct_assignment" title="cpp/language/operator assignment">assignment expression</a>, where list-initialization initializes the parameter of the overloaded <code>operator= </code>
</div>
<div class="t-li1">
<span class="t-li">11)</span> <a href="explicit_cast.html" title="cpp/language/explicit cast">functional cast expression</a> or other constructor invocations, where <i>braced-init-list</i> is used in place of a constructor argument. Copy-list-initialization initializes the constructor's parameter (note; the type U in this example is not the type that's being list-initialized; U's constructor's parameter is)</div>
<div class="t-li1">
<span class="t-li">12)</span> in a non-static <a href="data_members.html#Member_initialization" title="cpp/language/data members">data member initializer</a> that uses the equals sign</div>
<h3>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: Explanation">edit</a>]</span> <span class="mw-headline" id="Explanation">Explanation</span>
</h3>
<p>The effects of list initialization of an object of type <code>T</code> are:
</p>
 <table class="t-rev-begin">
<tr class="t-rev t-since-cxx17">
<td>
<ul>
<li> If <code>T</code> is a class type and the initializer list has a single element of the same or derived type (possibly cv-qualified), the object is initialized from that element (by copy-initialization for copy-list-initialization, or by direct-initialization for direct-list-initialization).
</li>
<li> Otherwise, if <code>T</code> is a character array and the initializer list has a single element that is an appropriately-typed string literal, the array is  <a href="aggregate_initialization.html#Character_arrays" title="cpp/language/aggregate initialization">initialized from the string literal as usual</a>
</li>
</ul>
</td>
<td><span class="t-mark-rev t-since-cxx17">(since C++17)</span></td>
</tr>
</table>
 <table class="t-rev-begin">
<tr class="t-rev t-until-cxx14">
<td>
<ul><li> If the braced-init-list is empty and <code>T</code> is a class type with a default constructor, <a href="value_initialization.html" title="cpp/language/value initialization">value-initialization</a> is performed.
</li></ul>
<ul><li> Otherwise, if <code>T</code> is an <a href="aggregate_initialization.html" title="cpp/language/aggregate initialization">aggregate type</a>, <a href="aggregate_initialization.html" title="cpp/language/aggregate initialization">aggregate initialization</a> is performed.
</li></ul>
</td>
<td><span class="t-mark-rev t-until-cxx14">(until C++14)</span></td>
</tr>
<tr class="t-rev t-since-cxx14">
<td>
<ul><li> If <code>T</code> is an <a href="aggregate_initialization.html" title="cpp/language/aggregate initialization">aggregate type</a>, <a href="aggregate_initialization.html" title="cpp/language/aggregate initialization">aggregate initialization</a> is performed.
</li></ul>
<ul><li> Otherwise, If the braced-init-list is empty and <code>T</code> is a class type with a default constructor, <a href="value_initialization.html" title="cpp/language/value initialization">value-initialization</a> is performed.
</li></ul>
</td>
<td><span class="t-mark-rev t-since-cxx14">(since C++14)</span></td>
</tr>
</table>
<ul><li> Otherwise, if <code>T</code> is a specialization of <span class="t-lc"><a href="../utility/initializer_list.html" title="cpp/utility/initializer list">std::initializer_list</a></span>, a new <code>std::initializer_list</code> prvalue of the same type is constructed and used to direct-initialize or copy-initialize the object of type <code>T</code>, depending on context.
</li></ul>
<ul><li> Otherwise, the constructors of <code>T</code> are considered, in two phases:
</li></ul>
<dl><dd>
<ul><li> All constructors that take <span class="t-lc"><a href="../utility/initializer_list.html" title="cpp/utility/initializer list">std::initializer_list</a></span> as the only argument, or as the first argument if the remaining arguments have default values, are examined, and matched by overload resolution against a single argument of type <span class="t-lc"><a href="../utility/initializer_list.html" title="cpp/utility/initializer list">std::initializer_list</a></span>
</li></ul>
</dd></dl>
<dl><dd>
<ul><li> If the previous stage does not produce a match, all constructors of <code>T</code> participate in overload resolution against the set of arguments that consists of the elements of the braced-init-list, with the restriction that only non-narrowing conversions are allowed. If this stage produces an explicit constructor as the best match for a copy-list-initialization, compilation fails (note, in simple copy-initialization, explicit constructors are not considered at all)
</li></ul>
</dd></dl>
<ul><li> Otherwise, if the braced-init-list has only one element and either <code>T</code> isn't a reference type or is reference type that isn't compatible with the type of the element, <code>T</code> is <a href="direct_initialization.html" title="cpp/language/direct initialization">direct-initialized</a> (in direct-list-initialization) or <a href="copy_initialization.html" title="cpp/language/copy initialization">copy-initialized</a> (in copy-list-initialization), except that narrowing conversions are not allowed.
</li></ul>
<ul><li> Otherwise, if <code>T</code> is reference type, a prvalue temporary of the referenced type is list-initialized, and the reference is bound to that temporary. (this fails if the reference is a non-const lvalue reference)
</li></ul>
<ul><li> Otherwise, if the braced-init-list has no elements, <code>T</code> is <a href="value_initialization.html" title="cpp/language/value initialization">value-initialized</a>.
</li></ul>
<h3>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: Narrowing conversions">edit</a>]</span> <span class="mw-headline" id="Narrowing_conversions">Narrowing conversions</span>
</h3>
<p>list-initialization limits the allowed <a href="implicit_cast.html" title="cpp/language/implicit cast">implicit conversions</a> by prohibiting the following:
</p>
<ul><li> conversion from a floating-point type to an integer type
</li></ul>
<ul><li> conversion from a <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">long</span> <span class="kw4">double</span></span></span> to <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">double</span></span></span> or to <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">float</span></span></span> and conversion from <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">double</span></span></span> to <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">float</span></span></span>, except where the source is a <a href="constant_expression.html" title="cpp/language/constant expression">constant expression</a> and overflow does not occur
</li></ul>
<ul><li> conversion from an integer type to a floating-point type, except where the source is a constant expression whose value can be stored exactly in the target type
</li></ul>
<ul><li> conversion from integer or unscoped enumeration type to integer type that cannot represent all values of the original, except where source is a constant expression whose value can be stored exactly in the target type
</li></ul>
<h3>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: Notes">edit</a>]</span> <span class="mw-headline" id="Notes">Notes</span>
</h3>
<p>A braced-init-list is not an expression and therefore has no type, e.g. <span class="t-c"><span class="mw-geshi cpp source-cpp">decltype<span class="br0">(</span><span class="br0">{</span><span class="nu0">1</span>,<span class="nu0">2</span><span class="br0">}</span><span class="br0">)</span></span></span> is ill-formed. Having no type implies that template type deduction cannot deduce a type that matches a braced-init-list, so given the declaration <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> T<span class="sy1">&gt;</span> <span class="kw4">void</span> f<span class="br0">(</span>T<span class="br0">)</span><span class="sy4">;</span></span></span> the expression <span class="t-lc">f({1,2,3})</span> is ill-formed. A special exception is made for <a href="template_argument_deduction.html#Other_contexts" title="cpp/language/template argument deduction">type deduction using the keyword <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">auto</span></span></span> </a>, which deduces any braced-init-list as <span class="t-lc"><a href="../utility/initializer_list.html" title="cpp/utility/initializer list">std::initializer_list</a></span>
</p>
<p>Also because braced-init-list has no type, <a href="overload_resolution.html#Implicit_conversion_sequence_in_list-initialization" title="cpp/language/overload resolution">special rules for overload resolution</a> apply when it is used as an argument to an overloaded function call.
</p>
<h3>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: Example">edit</a>]</span> <span class="mw-headline" id="Example">Example</span>
</h3>
<div class="t-example">
<div class="t-example-live-link"><div class="coliru-btn coliru-btn-run-init">Run this code</div></div>
<div dir="ltr" class="mw-geshi" style="text-align: left;"><div class="cpp source-cpp"><pre class="de1"><span class="co2">#include &lt;iostream&gt;</span>
<span class="co2">#include &lt;vector&gt;</span>
<span class="co2">#include &lt;map&gt;</span>
<span class="co2">#include &lt;string&gt;</span>
 
<span class="kw1">struct</span> Foo <span class="br0">{</span>
    <a href="../container/vector.html"><span class="kw1071">std::<span class="me2">vector</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> mem <span class="sy1">=</span> <span class="br0">{</span><span class="nu0">1</span>,<span class="nu0">2</span>,<span class="nu0">3</span><span class="br0">}</span><span class="sy4">;</span> <span class="co1">// list-initialization of a non-static member</span>
    <a href="../container/vector.html"><span class="kw1071">std::<span class="me2">vector</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> mem2<span class="sy4">;</span>
    Foo<span class="br0">(</span><span class="br0">)</span> <span class="sy4">:</span> mem2<span class="br0">{</span><span class="sy2">-</span><span class="nu0">1</span>, <span class="sy2">-</span><span class="nu0">2</span>, <span class="sy2">-</span><span class="nu0">3</span><span class="br0">}</span> <span class="br0">{</span><span class="br0">}</span> <span class="co1">// list-initialization of a member in constructor</span>
<span class="br0">}</span><span class="sy4">;</span>
 
<a href="../utility/pair.html"><span class="kw906">std::<span class="me2">pair</span></span></a><span class="sy1">&lt;</span><a href="../string/basic_string.html"><span class="kw1049">std::<span class="me2">string</span></span></a>, <a href="../string/basic_string.html"><span class="kw1049">std::<span class="me2">string</span></span></a><span class="sy1">&gt;</span> f<span class="br0">(</span><a href="../utility/pair.html"><span class="kw906">std::<span class="me2">pair</span></span></a><span class="sy1">&lt;</span><a href="../string/basic_string.html"><span class="kw1049">std::<span class="me2">string</span></span></a>, <a href="../string/basic_string.html"><span class="kw1049">std::<span class="me2">string</span></span></a><span class="sy1">&gt;</span> p<span class="br0">)</span>
<span class="br0">{</span>
    <span class="kw1">return</span> <span class="br0">{</span>p.<span class="me1">second</span>, p.<span class="me1">first</span><span class="br0">}</span><span class="sy4">;</span> <span class="co1">// list-initialization in return statement</span>
<span class="br0">}</span>
 
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
    <span class="kw4">int</span> n0<span class="br0">{</span><span class="br0">}</span><span class="sy4">;</span>     <span class="co1">// value-initialization (to zero)</span>
    <span class="kw4">int</span> n1<span class="br0">{</span><span class="nu0">1</span><span class="br0">}</span><span class="sy4">;</span>    <span class="co1">// direct-list-initialization</span>
    <a href="../string/basic_string.html"><span class="kw1049">std::<span class="me2">string</span></span></a> s1<span class="br0">{</span><span class="st0">'a'</span>, <span class="st0">'b'</span>, <span class="st0">'c'</span>, <span class="st0">'d'</span><span class="br0">}</span><span class="sy4">;</span> <span class="co1">// initializer-list constructor call</span>
    <a href="../string/basic_string.html"><span class="kw1049">std::<span class="me2">string</span></span></a> s2<span class="br0">{</span>s1, <span class="nu0">2</span>, <span class="nu0">2</span><span class="br0">}</span><span class="sy4">;</span>           <span class="co1">// regular constructor call</span>
    <a href="../string/basic_string.html"><span class="kw1049">std::<span class="me2">string</span></span></a> s3<span class="br0">{</span><span class="nu12">0x61</span>, <span class="st0">'a'</span><span class="br0">}</span><span class="sy4">;</span> <span class="co1">// initializer-list ctor is preferred to (int, char)</span>
 
    <span class="kw4">int</span> n2 <span class="sy1">=</span> <span class="br0">{</span><span class="nu0">1</span><span class="br0">}</span><span class="sy4">;</span> <span class="co1">// copy-list-initialization</span>
    <span class="kw4">double</span> d <span class="sy1">=</span> <span class="kw4">double</span><span class="br0">{</span><span class="nu16">1.2</span><span class="br0">}</span><span class="sy4">;</span> <span class="co1">// list-initialization of a temporary, then copy-init</span>
 
    <a href="../container/map.html"><span class="kw1077">std::<span class="me2">map</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span>, <a href="../string/basic_string.html"><span class="kw1049">std::<span class="me2">string</span></span></a><span class="sy1">&gt;</span> m <span class="sy1">=</span> <span class="br0">{</span> <span class="co1">// nested list-initialization</span>
           <span class="br0">{</span><span class="nu0">1</span>, <span class="st0">"a"</span><span class="br0">}</span>,
           <span class="br0">{</span><span class="nu0">2</span>, <span class="br0">{</span><span class="st0">'a'</span>, <span class="st0">'b'</span>, <span class="st0">'c'</span><span class="br0">}</span> <span class="br0">}</span>,
           <span class="br0">{</span><span class="nu0">3</span>, s1<span class="br0">}</span>
    <span class="br0">}</span><span class="sy4">;</span>
 
    <a href="../io/cout.html"><span class="kw1453">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> f<span class="br0">(</span><span class="br0">{</span><span class="st0">"hello"</span>, <span class="st0">"world"</span><span class="br0">}</span><span class="br0">)</span>.<span class="me1">first</span> <span class="co1">// list-initialization in function call</span>
              <span class="sy1">&lt;&lt;</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
 
    <span class="kw4">const</span> <span class="kw4">int</span> <span class="br0">(</span><span class="sy3">&amp;</span>ar<span class="br0">)</span><span class="br0">[</span><span class="nu0">2</span><span class="br0">]</span> <span class="sy1">=</span> <span class="br0">{</span><span class="nu0">1</span>,<span class="nu0">2</span><span class="br0">}</span><span class="sy4">;</span> <span class="co1">// binds a lvalue reference to a temporary array</span>
    <span class="kw4">int</span><span class="sy3">&amp;&amp;</span> r1 <span class="sy1">=</span> <span class="br0">{</span><span class="nu0">1</span><span class="br0">}</span><span class="sy4">;</span> <span class="co1">// binds a rvalue reference to a temporary int</span>
<span class="co1">//  int&amp; r2 = {2}; // error: cannot bind rvalue to a non-const lvalue ref</span>
 
<span class="co1">//  int bad{1.0}; // error: narrowing conversion</span>
    <span class="kw4">unsigned</span> <span class="kw4">char</span> uc1<span class="br0">{</span><span class="nu0">10</span><span class="br0">}</span><span class="sy4">;</span> <span class="co1">// okay</span>
<span class="co1">//  unsigned char uc2{-1}; // error: narrowing conversion</span>
 
    Foo f<span class="sy4">;</span>
 
    <a href="../io/cout.html"><span class="kw1453">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> n0 <span class="sy1">&lt;&lt;</span> <span class="st0">' '</span> <span class="sy1">&lt;&lt;</span> n1 <span class="sy1">&lt;&lt;</span> <span class="st0">' '</span> <span class="sy1">&lt;&lt;</span> n2 <span class="sy1">&lt;&lt;</span> <span class="st0">'<span class="es1">\n</span>'</span>
              <span class="sy1">&lt;&lt;</span> s1 <span class="sy1">&lt;&lt;</span> <span class="st0">' '</span> <span class="sy1">&lt;&lt;</span> s2 <span class="sy1">&lt;&lt;</span> <span class="st0">' '</span> <span class="sy1">&lt;&lt;</span> s3 <span class="sy1">&lt;&lt;</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
    <span class="kw1">for</span><span class="br0">(</span><span class="kw4">auto</span> p<span class="sy4">:</span> m<span class="br0">)</span>
        <a href="../io/cout.html"><span class="kw1453">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> p.<span class="me1">first</span> <span class="sy1">&lt;&lt;</span> <span class="st0">' '</span> <span class="sy1">&lt;&lt;</span> p.<span class="me1">second</span> <span class="sy1">&lt;&lt;</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
    <span class="kw1">for</span><span class="br0">(</span><span class="kw4">auto</span> n<span class="sy4">:</span> f.<span class="me1">mem</span><span class="br0">)</span>
        <a href="../io/cout.html"><span class="kw1453">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> n <span class="sy1">&lt;&lt;</span> <span class="st0">' '</span><span class="sy4">;</span>
    <span class="kw1">for</span><span class="br0">(</span><span class="kw4">auto</span> n<span class="sy4">:</span> f.<span class="me1">mem2</span><span class="br0">)</span>
        <a href="../io/cout.html"><span class="kw1453">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> n <span class="sy1">&lt;&lt;</span> <span class="st0">' '</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div></div>
<p>Output:
</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;"><div class="text source-text"><pre class="de1">world
0 1 1
abcd cd aa
1 a
2 abc
3 abcd
1 2 3 -1 -2 -3</pre></div></div> 
</div>
<p><br>
</p>
<h3>
<span class="editsection">[<a href="http%3A//en.cppreference.com/mwiki/index.php" title="Edit section: See also">edit</a>]</span> <span class="mw-headline" id="See_also">See also</span>
</h3>
<ul>
<li> <a href="default_initialization.html" title="cpp/language/default initialization">default initialization</a>
</li>
<li> <a href="direct_initialization.html" title="cpp/language/direct initialization">direct initialization</a>
</li>
<li> <a href="aggregate_initialization.html" title="cpp/language/aggregate initialization">aggregate initialization</a>
</li>
<li> <a href="copy_initialization.html" title="cpp/language/copy initialization">copy initialization</a>
</li>
</ul>

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